Heat the water, sugar and apricot brandy until the sugar has dissolved.
Bring the apricots, sugar, water and lemon juice to the boil, then cover and simmer over a medium heat for approx. 15 minutes until soft, puree.
Mix the sour cream with powdered sugar.
Fill half of the amarettini into 4 glasses, drizzle with the water-schnapps mixture. Pour in half of the apricot puree, then pour half of the cream over it. To repeat. Cover and chill for 2-3 hours.
Decorate with the second half of the crumbled amarettinis.